What can cause hyperhidrosis?

Hi doctor,

I am a 15 year old boy and I have hyperhidrosis. I sweat so much. My shirt cannot stay on for at least 5 minutes. In some half an hour to one hour my whole shirt and armpit area will drench in sweat. Yes, I take a shower twice a day and put deodorant every day. I have even tried the antiperspirant deodorant, but that did not stop it and I think it made it worse. I really want to believe it is just puberty as this has been going on since I was 12 or 13. But, something tells me that it is not because of puberty. Everyone else at school does not have this problem and some relatives in my family has it too. Just like my shirt, my pants will start soaking after 30 minutes of sitting down. I really want a diagnosis or close to one before I actually go to a doctor as I have not yet regarding my issue. Also are there any home remedies or other over-the-counter deodorant to help minimize this issue or completely stop it? I am really fit and regularly lift weights, play lots of sports (soccer, boxing, etc.,) and keep my body in good shape. I know that weight lifting could not be a problem if that was a suggestion. I sweat a lot when I am in social places such as school or when I go out. It is not because of anxiety, but I rarely feel nervous when my arms are getting drenched. This is a more serious problem in the morning either at home or at a social place and gradually calms during the afternoon when I am at home. It is so bad that my armpits can drench two layers of clothing. For example, if I wear a shirt and a jacket over it, then it does not really matter how many layers and by the end of the day my clothing will be soaked in sweat. I do not really have any symptoms besides the fact that I am always on alert when I am out. This is really embarrassing and I have no idea what to do about this. Please help.